Method and system for spatial static map construction

Abstract

A method and a system for spatial static map construction are provided. In the method, a three-dimensional space is scanned by using a LiDAR sensor to generate a LiDAR frame including multiple points in the three-dimensional space in a time sequence. As for each point in the LiDAR frame, a corresponding point closest to the point is found from a static map built according to the three-dimensional space, and a distance from the corresponding point is calculated. The point is labelled as a dynamic point if the distance is greater than a threshold, and otherwise labelled as a static point. Each labelled dynamic point is compared with points in N LiDAR frames generated before the time sequence, and corrected as a static point if included in the N LiDAR frames. The dynamic points in the LiDAR frame are removed, and each static point is updated to the static map.

What is claimed is: 
     
         1 . A method for spatial static map construction, adapted for an electronic device with a processor, wherein the method comprises steps as follows:
 scanning a three-dimensional space with a LiDAR sensor to generate a LiDAR frame comprising a plurality of points in the three-dimensional space in a time sequence;   for each of the points in the LiDAR frame, finding a corresponding point closest to the point of the LiDAR frame from a static map built according to the three-dimensional space and calculating a distance between the point and the corresponding point, wherein the point is labelled as a dynamic point if the distance is greater than a predetermined threshold, and the point is labelled as a static point if the distance is not greater than the predetermined threshold;   comparing each of the dynamic points labelled in the LiDAR frame with a plurality of points in N LiDAR frames generated before the time sequence, wherein if it is determined that the N LiDAR frames comprise the dynamic point, the dynamic point is corrected as the static point, where N is a positive integer; and   removing the dynamic point in the LiDAR frame and updating each of the static points in the LiDAR frame to the static map.   
     
     
         2 . The method for spatial static map construction according to  claim 1 , further comprising:
 performing posture conversion on the generated LiDAR frame so that a coordinate axis of the converted LiDAR frame is consistent with a coordinate axis of the static map.   
     
     
         3 . The method for spatial static map construction according to  claim 2 , wherein the step of performing the posture conversion on the LiDAR frame comprises:
 performing the posture conversion on the LiDAR frame through simultaneous localization and mapping (SLAM) technology.   
     
     
         4 . The method for spatial static map construction according to  claim 1 , wherein after the step of generating the LiDAR frame comprising the points in the three-dimensional space in the time sequence, the method further comprises:
 determining whether the LiDAR frame is a first LiDAR frame generated by the LiDAR sensor; and   directly updating the LiDAR frame to the static map if the LiDAR frame is the first LiDAR frame and setting a coordinate axis of the static map based on a coordinate axis of the LiDAR frame.   
     
     
         5 . The method for spatial static map construction according to  claim 1 , further comprising:
 repeating the steps, continuously using the LiDAR sensor to scan the three-dimensional space to generate LiDAR frames in different time sequences and to update the static map, and stopping the LiDAR sensor when the three-dimensional space is completely scanned.   
     
     
         6 . The method for spatial static map construction according to  claim 1 , wherein the distance between the point of the LiDAR frame and the corresponding point of the static map is Euclidean distance. 
     
     
         7 . A system for spatial static map construction, comprising a LiDAR sensor and a processing device,
 wherein the processing device comprises a processor and is connected to the LiDAR sensor, and the processor is configured to:   scan a three-dimensional space with the LiDAR sensor to generate a LiDAR frame comprising a plurality of points in the three-dimensional space in a time sequence;   for each of the points in the LiDAR frame, find a corresponding point closest to the point of the LiDAR frame from a static map built according to the three-dimensional space and calculate a distance between the point and the corresponding point, wherein the point is labelled as a dynamic point if the distance is greater than a predetermined threshold, and the point is labelled as a static point if the distance is not greater than the predetermined threshold;   compare each of the dynamic points labelled in the LiDAR frame with a plurality of points in N LiDAR frames generated before the time sequence, wherein if it is determined that the N LiDAR frames comprise the dynamic point, the dynamic point is corrected as the static point, where N is a positive integer; and   remove each of the dynamic points in the LiDAR frame and update the static points in the LiDAR frame to the static map.   
     
     
         8 . The system for spatial static map construction according to  claim 7 , wherein the processor further performs posture conversion on the generated LiDAR frame so that a coordinate axis of the converted LiDAR frame is consistent with a coordinate axis of the static map. 
     
     
         9 . The system for spatial static map construction according to  claim 8 , wherein the processor performs the posture conversion on the LiDAR frame through simultaneous localization and mapping (SLAM) technology. 
     
     
         10 . The system for spatial static map construction according to  claim 7 , wherein the processor further determines whether the LiDAR frame in the time sequence is a first LiDAR frame generated by the LiDAR sensor, if the LiDAR frame is the first LiDAR frame, the LiDAR frame is directly updated to the static map, and a coordinate axis of the static map is set based on a coordinate axis of the LiDAR frame. 
     
     
         11 . The system for spatial static map construction according to  claim 7 , wherein the processor further repeats the steps, continuously uses the LiDAR sensor to scan the three-dimensional space to generate LiDAR frames in different time sequences and to update the static map, and stops the LiDAR sensor when the three-dimensional space is completely scanned. 
     
     
         12 . The system for spatial static map construction according to  claim 7 , wherein the distance between the point of the LiDAR frame and the corresponding point of the static map is Euclidean distance. 
     
     
         13 . The system for spatial static map construction according to  claim 7 , further comprising:
 a self-propelled vehicle, wherein the LiDAR sensor is configured on the self-propelled vehicle to generate the LiDAR frame comprising the points in the three-dimensional space when the self-propelled vehicle is traveling in the three-dimensional space.   
     
     
         14 . The system for spatial static map construction according to  claim 13 , wherein the processor further controls the self-propelled vehicle to travel in the three-dimensional space, and during a traveling process of the self-propelled vehicle, continuously uses the LiDAR sensor to scan the three-dimensional space to generate LiDAR frames in different time sequences and to update the static map until the self-propelled vehicle travels the entire three-dimensional space.